Portugese District
The said middle class of the Tejuco, for example, started to compose the responsible guard for the patrolling of the district. The composed ruling class of Portuguese and descendants started to occupy the positions of the Real Extration. The slaves who before worked for the contract-holders had been rented for the real Extration, that paid to its daily gentlemen for the service. Exactly with this change in the exploration of diamonds the other activities had continued having importance, activities that were exerted inside and outside of the landmark and that they had participation of some citizens of the arraial. A great parcel of the population possua enslaved rented for the Real Extration and many of them lived of the paid rent for the Meeting. When the Crown thought about revoking the monopoly of diamonds in the 1803, population that lived of this rent was fearful to lose this important source of income and to prevent a collapse of the local economy was necessary that the Crown gave up for a time of this measure. A revocation of the monopoly would harm considerably the population of the arraial that already had consolidated its economy in the Real Extration and the crown having suppressed the monopoly certainly would take the arraial and region to the ruin.
The naturalist Auguste de Saint-Hilaire observed in 1817 in the book Trip for the District of Diamonds and the coast of the Brasilalgumas singularidades of Diamantina as, for example, the strong existing commerce in the arraial, exactly this being rigorously controlled for the Intendant. This is an indication of as Diamantina was the center of the commerce of all the region. It also observes that it was about as the more important population nucleus of Mines after the capital, Rich Village, current Ouro Preto. The Diamantino District existed until the year of 1821 when then it was extintodevido to the incompatibility of the Regiment with the laws promulgated in the Liberal Revolution of the Port. .